In a wireless communication system, a data stream will most likely experience multiple reflections (multipath) while propagating between the transmitter and the receiver. Multipath fading refers to a phenomenon, in which a transmitted signal is reflected by various obstacles within a transmission medium, which causes the transmitted signal to traverse a plurality of different transmit paths within the transmission medium. The transmitted signal in each of the multipaths reaches a receiving antenna at different times since each multipath possesses a different time delay. With advancements in communication technologies, wireless communication systems that originally utilized a single transmit antenna and a single receive antenna, may now use multiple antennas at the transmission end and/or at the receiver end to improve signal detection. Wireless communication systems which rely on multiple transmit and/or receiver antennas may utilize one or more packet preambles to facilitate signal detection and further signal processing.
In a conventional frequency-sparse packet preamble systems, large errors may occur in the power estimates of received signals, especially for channels that possess long delay-spreads. Moreover, the number of disjoint sets of tones which may be used is limited by the total number of tones available in a legacy preamble. Additionally, conventional frequency-sparse packet preamble systems may require multiple signal carriers for operation, which may increase the complexity of associated circuitry and also increases cost of implementation.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.